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Number theory Difficulty 3.0 AMC 10/12 Find the answer United Kingdom

Noah writes down the numbers 1, 2, 4 and 13. He then adds a fifth integer xx which then becomes the mean, median or mode of the five numbers. How many possible choices for xx are there?

(A) 22 (B) 33 (C) 44 (D) 55 (E) 66

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